In the early 1960s the only significant Electro-Optic (E-O) systems in use by the military were telescopic sights, television systems, and image intensifier systems. The invention of the laser in 1960 allowed laser rangefinder/designator systems to be integrated directly with imaging systems. Laser guided weapon systems were further enhanced by the introduction of TV-aided aiming systems on stabilized platforms. These were followed by thermal imagers, such as Forward Looking Infrared (FLIR) systems which achieved day/night capability.
Today's military arsenals contain FLIR and laser systems as standard pieces of equipment. The proliferation of FLIRs and lasers under armor, in attack and surveillance aircraft, aboard ship, with ground personnel, and so forth, has reached dramatic proportions. Improved guidance, accuracy, and maneuverability in weapons employing these systems has put increased demands on the platform, the sensors, and the operator. To help the user, autotrackers have been added in order to automatically track various targets. The introduction of such sophisticated and complex electro-optic technologies to the field has put increased and unique demands on the logistics support personnel and equipment. Commensurate with the hardware is the necessity to field the sophisticated maintenance support equipment required to keep this important capability on line and operating.
However, imaging systems in use today typically use electro-optic sensors on board a platform which must be fully functional and accurately boresighted with each other if the sensors are to be of any use. Any number of events, such as a nearby bomb blast, or even the constant mechanical vibration of the platform, can cause the sensors to fall out of alignment. Therefore, it is necessary to have a boresight test system that can be used any time the boresight accuracy of the sensors is in question.
The task of boresighting integrated sensors is never a simple one. Materials and techniques employed in the boresighting apparatus must be suited to the specific wavelength bands over which the sensors are expected to perform. The problem is particularly complex when a set of sensors combines electro-optic functions in widely disparate spectral bands. The combination of video (0.4 to 0.7 micrometers), FLIR (3 to 5 and 8 to 12 micrometers), and Nd:YAG laser rangefinder/designators (1.06 micrometers) places design constraints on the test equipment.
It is an object of the present invention, therefore, to provide a system which will permit accurate and rapid boresighting of a plurality of discrete components.
It is another object of the present invention to provide such a boresighting system which is passive in nature.
It is still another object of the present invention to provide such a system with a member which is optically pumped for stimulated emission of radiation to provide the target for the boresighting operation.
It is a further object of the present invention to provide such a system which is operable simultaneously in discrete spectral bands.